Variations in Cerebral Haemodynamics during Irrigation Phase in Neuroendoscopic Procedures

Not many centres measure intracranial pressure during an endoscopic procedure. However, if the irrigation fluid during endoscopy is not simultaneously drained, then some rise in intracranial pressure can be anticipated. This study was carried out to measure and monitor changes in intracranial pressure during the irrigation phase in a neuroendoscopic procedure using a Codman catheter placed in the parenchyma. Intracranial pressure was monitored in 13 patients undergoing surgical neuroendoscopic procedures under a standardised anaesthetic technique. Heart rate, mean arterial pressure, intracranial pressure and cerebral perfusion pressure were recorded at baseline and during the irrigation phase of the procedure. The heart rate during irrigation was comparable to baseline values, but the mean arterial pressure at the time of irrigation increased an average of 7 mmHg (P =0.02). At the same time there was an average 34 mmHg increase in intracranial pressure (P <0.001), producing an average 26 mmHg decrease in the cerebral perfusion pressure (P <0.001) during irrigation. There was an average of four episodes of raised intracranial pressure (> 25 mmHg) during the irrigation phase per patient. We suggest that the intracranial pressure be routinely monitored during neuroendoscopic procedures. Only then can the potential adverse effect of irrigation on intracranial pressure and cerebral perfusion pressure be assessed.

Bilateral vocal cord palsy due to brain-stem cavernoma--a diagnostic dilemma!

Vocal cord palsy may result from varied causes. However, cord palsy resulting from a brain-stem cavernoma has never been reported. We report a patient with vocal cord palsy in a 30-year-old male resulting from the brain-stem lesion. The patient became symptomatic each time the lesion bled and improved gradually when the bleeding resolved. Repeated insults on the brain-stem produced permanent cord palsy. Although a rare presentation, brain-stem cavernoma may be considered in the aetiology of cord palsy.

Posterior fossa haematoma following sudden decompression of acute hydrocephalus resulting from neuroendoscopy

We report a case of a 47-year-old male undergoing endoscopic removal of a third ventricular colloid cyst. After uneventful surgery, the patient remained drowsy and was transferred to the intensive care unit for supportive care. In the postoperative period, the patient developed hydrocephalus due to clot in the region of the cyst. A posterior fossa haematoma and further neurological deterioration complicated external ventricular drainage, presumably due to sudden intracranial hypotension. Gradual ventricular decompression is recommended to reduce the risk of this complication.

Pulmonary oedema following venous air embolism during transsphenoidal pituitary surgery

Venous air embolism (VAE) is a well known complication in procedures where the operative field is above the level of the heart. Acute pulmonary oedema after a large air embolus occurring during neurosurgery is also a recognized phenomenon. However, pulmonary oedema following repeated episodes of VAE in sublabial transsphenoidal (SLTS) surgery for pituitary adenoma has never been reported. We describe a case of VAE in a 65 year old male undergoing SLTS surgery for pituitary adenoma. Following this, the patient had pulmonary oedema which resolved on supportive treatment. Pulmonary oedema as a result of VAE may go unrecognised intraoperatively but can lead to a significant postoperative morbidity. Early suspicion and recognition of VAE and institution of aggressive treatment will help to avoid fatal consequences.

Spontaneous spinal epidural haematoma: a rare cause of quadriplegia in the post-partum period

Spontaneous spinal epidural haematoma (SSEH) is a rare cause of neurological deficit in the pregnant and post-partum patients. However, SSEH with associated myelitis presenting as quadriplegia and respiratory paralysis in the post-partum period has never been reported. We report the development of acute onset quadriplegia progressing to respiratory arrest in a 24-yr-old woman 2 weeks after normal vaginal delivery. There was no history suggestive of any coagulopathy (inherited or acquired), eclampsia, pre-existing neurological deficit, or iatrogenic manipulations such as spinal/epidural injections. Magnetic resonance imaging revealed a posterior epidural haematoma extending from C4-C7 and areas of signal changes in spinal cord from cervicomedullary junction to D5 level (suggestive of demyelination). We highlight this rare cause of quadriplegia; focusing on the altered dynamics of the epidural vasculature in the peripartum period leading to SSEH.

Intracranial Pressure Changes During Valsalva Manoeuvre in Patients Undergoing a Neuroendoscopic Procedure

BACKGROUND

The Valsalva manoeuvre results in an increase in intrathoracic pressure which alters the systemic and cerebral circulations significantly. We decided to record changes in the intracranial pressure and cerebral perfusion pressure resulting from a Valsalva manoeuvre in anaesthetised patients.

METHODS

11 patients of either gender submitted to surgical neuroendoscopic procedures were studied. Standard general anaesthesia was maintained for the procedure in all the patients. Passive Valsalva manoeuvres were carried out by squeezing the bag of the closed breathing circuit to maintain an airway pressure of 20 cm H2O above peak inspiratory airway pressure for 10 seconds. The variables heart rate, mean arterial pressure, intracranial pressure and cerebral perfusion pressure were noted. The variables were recorded again after the surgical correction. All cardiovascular and cerebrovascular variables were compared using the Wilcoxon sign-rank test. We considered a value of p less than 0.05 to be statistically significant.

RESULTS

The median age of the 11 patients was 22 years (range: 15-43) and median weight was 50 kg (range: 30-78). On comparing the variables during the two Valsalva manoeuvres, we found significant changes in HR, ICP and CPP after the surgical correction. No complications were encountered in any of the patients.

CONCLUSION

There was a significant reduction in cerebral perfusion pressure during the Valsalva manoeuvre in both stages. This was a result of change in either the intracranial pressure or the mean arterial pressure. Although our patients did not suffer a clinically significant reduction in cerebral perfusion pressure and so had an uneventful recovery, the effect of Valsalva manoeuvre on cerebral perfusion pressure cannot be denied. The marked haemodynamic changes clearly warrant a cautious use of this manoeuvre in neurosurgical practice.

Haemodynamic changes after intracisternal papaverine instillation during intracranial aneurysmal surgery

Cerebral vasospasm remains a significant cause of mortality and morbidity after aneurysmal subarachnoid haemorrhage. Use of either intra-arterial or intracisternal papaverine as an alternative treatment of refractory cerebral vasospasm has been associated with various complications including haemodynamic instabilities. However, our search in literature did not reveal association of bradycardia and hypotension with the use of papaverine by either of these routes. Here, we describe a case of anterior communicating artery aneurysm with hydrocephalus. The patient underwent craniotomy and clipping of the aneurysm followed by third ventriculostomy. Instillation of papaverine at the surgical site caused significant haemodynamic changes possibly because of stimulation of hypothalamus in the third ventricle or vagal nuclei in the fourth ventricle, or even both. We recommend cautious use of intracisternal papaverine in such scenario especially when third ventriculostomy has been performed as an adjunct surgical procedure.

Lidocaine infiltration of the scalp does not completely abolish increased intraocular pressure due to skull pin insertion

Insertion of skull pins results in haemodynamic perturbations, which can be blunted by local anaesthetic infiltration of the pin sites. No study has assessed the effects on intraocular pressure. General anaesthesia was induced in 71 patients undergoing cervical spine surgery with attachment of Gardner Wells tongs to the skull. Skull pins were attached five minutes after induction following either saline (group I, 35 patients) or lidocaine (group II, 36 patients) infiltration of scalp. Intraocular pressure, mean arterial pressure and heart rate were recorded before (baseline), immediately after, and 60 s following pin insertion and analysed statistically. Insertion of pins increased intraocular pressure in both groups (from 8.4+/-2.7 to 14.2+/-3.0 mmHg in group I, and from 8.8+/-2.3 to 12.7+/-2.7 mmHg in group II, P < 0.001), which persisted even at 60 s but the increase was significantly greater in group I. Insertion of pins significantly increased blood pressure in group I only. We conclude that lidocaine infiltration at the skull pin sites for Gardner Wells tong attachment fails to completely abolish increased intraocular pressure.

Sudden asystole during surgery in the cerebellopontine angle

We report a case of a 40-year-old lady undergoing surgery for a tumor in the cerebellopontine angle. Intraoperatively, patient had a sudden asystole without prior warning sign of bradycardia. It could have been the severe form of trigeminocardiac reflex. The cardiac rhythm returned spontaneously once the surgical manipulation stopped. The remainder of the operation was uneventful and no complication occurred afterwards. The possible mechanism of the event is discussed.

Intracranial pressure and haemodynamic changes during the tunnelling phase of ventriculoperitoneal shunt insertion

BACKGROUND AND OBJECTIVE

The tunnelling phase of ventriculoperitoneal shunt insertion is the most painful part but patients are often given inadequate opioid analgesic for fear of post operative delayed recovery and/or respiratory depression. This may result in an increase in intracranial pressure.

METHODS

Twenty adults scheduled to undergo ventriculoperitoneal shunt insertion were administered standard anaesthesia. Monitoring included heart rate, electrocardiogram, end-tidal carbon dioxide, invasive blood pressure, and oxygen saturation. Intracranial pressure was monitored by placing the ventricular end of shunt catheter in the dilated lateral ventricle. Five minutes before tunnelling, fentanyl 1 microg kg(-1) was administered. Mean arterial pressure, heart rate and intracranial pressure were recorded during tunnelling and subsequently at 1-min interval for 5 min. Data were analysed using t-test and repeated measured test.

RESULTS

Tunnelling caused significant increase in mean arterial pressure (from 81.4 +/- 11.0 to 110.9 +/- 15.3 mmHg, P < 0.05), intracranial pressure (from 21.4 +/- 8.1 to 29.2 +/- 12.5 mmHg, P < 0.05) and heart rate (from 74.4 +/- 13.8 to 94.1 +/- 17.8 beats min(-1), P < 0.05). Whereas, the increase in haemodynamic parameters persisted for 3 min post-tunnelling, elevated intracranial pressure lasted for 2 min.

CONCLUSION

Tunnelling significantly increases intracranial pressure and blood pressure despite prior fentanyl administration. This may be deleterious in the presence of intracranial pathology.

Rupture of aorta and inferior vena cava during lumbar disc surgery

Major vascular injury during lumbar disc surgery has been recognized as an unusual but well described complication. A potentially fatal outcome can be avoided by a high index of suspicion and an early diagnosis. We present a rare case of aortic and inferior vena caval injury in a 50-year-old female patient undergoing intervertebral disc surgery at lumbar one and two levels. A quick diagnosis and prompt management resulted in a favourable outcome for the patient.

Dengue haemorrhagic fever outbreak in October-November 1996 in Ludhiana, Punjab, India

An epidemic of haemorrhagic fever broke out in Ludhiana in October and November 1996. Persons of all age groups were affected with preponderance of young adults. Haemorrhagic manifestations like rashes, epistaxis, bleeding from the gums and haematemesis were observed. The cause of fever was investigated. Serum samples collected at random from 71 patients were tested by ELISA for dengue types 1-4 IgM antibodies. These were positive in 96.7 per cent of cases. Immunoblot testing for IgM and IgG for all serotypes of dengue virus were positive in 90.2 and 73.2 per cent of the serum samples respectively. The haemorrhagic fever was serologically proven to be due to dengue virus.

Prevalence of multi-drug resistant Salmonella typhi in Ludhiana Punjab

A total of 945 strains of S. typhi isolated from blood cultures during 1989 to 1994 were studied. Their antibiotic susceptibility showed 580 (61.4%) of strains to be multidrug resistant. The 464 strains tested for their susceptibility to ciprofloxacin were all sensitive to the drug. Twenty three (17.9%) of the 128 strains of S. paratyphi A were resistant to chloramphenicol. The sole isolate of S. paratyphi B was sensitive to all antibiotics tested.

Predictive utility of clinical and stool parameters in bacterial diarrhoea in children

A prospective one year study was conducted on children between the ages of 1 month to 5 years hospitalised in the pediatric ward of Christian Medical College, Ludhiana, with the aim of determining the predictive utility of certain clinical and stool parameters in diagnosing bacterial diarrhoea. Among the 204 children enrolled in the study, fever was observed in 40% in both the culture positive and negative groups. Clinical features such as abdominal distension, vomiting and oliguria although had low positive predictive values, their negative predictive values were high. Among the stool parameters, watery consistency and pus cells > 5 HPF were significantly more often observed in culture positive cases. The presence of mucus and pus cells > 5 HPF had good sensitivity (70-80%) but poor specificity (27-40%), while the reverse was true of blood (sensitivity 23%, specificity 89%). Again the positive predictive values were uniformly low while the negative ones were high. In conclusion the clinical and stool parameters were found to be more useful by their absence than by their presence in excluding a positive stool culture.

Prevalence of hepatitis A, B, C & D in Ludhiana

172 sera were tested for serological markers of hepatitis A, hepatitis B, hepatitis C and hepatitis D to define the aetiology of acute viral hepatitis by Enzyme immunoassays. The viral aetiology could be decided in 60.5% (104/ 172) of patients. Hepatitis B infection was present in 34.9%, hepatitis A in 10.5%, hepatitis C in 9.3% and hepatitis D in 5.8% of cases. Delta hepatitis associated with HBsAg positive hepatitis was detected in 10% (6/60) of the patients. The aetiology remained undecided in 39.5% of patients.

Shigella isolates in stool

A total of 447 Shigella strains were isolated from stool samples during 1989-1991. Of these 270 (60%) were from children. Among the different species and serotypes Sh. flexneri 60 (13.4%) and Sh. sonnei Phage 139 (65%) were the most frequently isolated strains. 154 (34.4%) strains were resistant to three and 179 (40%) to more than three antibiotics. Some strains of Shigella were found to be resistant to furazolidine and neomycin.

Outbreak of gastroenteritis due to a new strain of non O group 1 Vibrio cholerae, in Ludhiana in May-August 1993

The isolation of the new serotype 0139 of non 01 V. cholerae from an outbreak of gastroenteritis is reported. The study of 35 such isolates revealed their similarity with the El tor vibrios biochemically and by other characters. All were strongly haemolytic and 97.1 per cent of the strains showed a positive haemagglutination.

Acinetobacter meningitis

10,468 CSF samples from cases of meningitis in different age groups were cultured during 1988-1991. Acinetobacter calcoaceticus was isolated in 12 (5.6%) of 211 positive cultures. The strain were 100% resistant to ampicillin, cotrimoxazole and tetracycline 50% resistant to cephazolin gentamicin and kanamycin but 100% susceptible to chloramphenicol.

Physical factors contributing to the partition coefficient and retention time of 2',3'-dideoxynucleoside analogues

Acquired immunodeficiency syndrome (AIDS) is an immunosuppressive disease characterized by an immune impairment and a high susceptibility to unusual forms of certain neoplasms. Since the brain is an important site of the infection, it is necessary to explore new classes of drugs that have the ability to penetrate across the blood-brain barrier, and the potency to suppress viral replication within the central nervous system (CNS). Therefore, the ability to predicate the lipophilicity of the potent anti-AIDS drugs may provide useful information about the potential of the drugs to enter CNS. In this paper, the correlations of log P (octanol-buffer partition coefficient) and log tR (retention time in HPLC; Rt was used by Balzarini et al.) with some physical constants like log MW (molecular weight), hydrogen bond forming ability (HB) of the substituents, and the substituent group dipole moments (mu) are analyzed. Good correlations of log P and log tR with log MW, HB, and mu have been obtained.

Anaerobic bacterial flora of wound sepsis

Two hundred specimens from wound infection (surgical and non-surgical) were cultured for the isolation of anaerobic and aerobic bacteria. Positive cultures were obtained in 174 (87%) and 26(13%) were sterile. Anaerobes were isolated from 31(17.8%), as single culture in 6(3.4%) and as mixed culture with aerobes in 25(14.3%). Amongst anaerobes, anaerobic cocci were predominant (45.9%). Of aerobes Staph pyogenes (35%) was predominant. Metronidazole was the most effective drug against anaerobes and gentamicin against aerobes. No significant difference was noted in antimicrobial susceptibility of anaerobes of surgical and non-surgical wounds. Among aerobes high resistance was observed in surgical wounds.

Haemagglutination antibody titres & immunoglobulin levels in cases of Plasmodium infection

Malarial antibody estimation was done in patients with malaria (50), and fever (malaria negative, 50) and in 50 healthy controls who gave no history of malaria for the last one year, using the indirect haemagglutination test (IHA). Seropositivity was 78, 32 and 4 per cent respectively. Levels of IgG and IgM were found to be significantly higher in patients as compared to controls and a significant fall was observed in IgA levels in patients of malaria. Although the malarial antibody titre showed good correlation with IgG (P less than 0.01) and IgM (P less than 0.05) not all patients with a negative haemagglutination antibody titre had normal immunoglobulin levels.

Carcinogen induced DNA damage in isolated rat liver nuclei

Alkali-labile DNA lesions were detected by a hydroxylapatite batch assay following incubation of isolated rat liver nuclei with direct and indirect-acting alkylating agents. N-Methyl-N'-nitro-N-nitrosoguanidine (MNNG) (20-200 microM) produced a steep, concentration-related decrease in double stranded DNA. In contrast, only minimal effects on DNA integrity were observed with methylmethane sulfonate (200 microM). The bifunctional alkylating agent, mechlorethamine produced an apparent increase in double-stranded DNA in accord with its ability to induce interstrand DNA crosslinks. The indirect-acting alkylating agent, dimethylnitrosamine (DMN) induced DNA damage only when an NADPH generating system was included in the incubation mixture. These results suggest that isolated rat liver nuclei may be a useful model for studying the effects of mutagenic and carcinogenic chemicals on the integrity of chromosomal DNA.